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Application. This set of eight (8) Two Heat Range Cooler NGK Iridium IX Performance Spark Plugs are specifically designed for the 2003-2004 SVT Cobra and 2007-2014 Shelby GT500 Mustangs that are running more boost.

Most Helpful Reviews

5/5

Modified gt500 2010

I added these plugs with a pulley/idler and cai tuner kit, as well as afco racing radiator and 170 thermostat. Very pleased with the responsiveness of the engine now and the plugs fit very well for the ...
modifications done. Would recommend these plugs for anyone looking to do minor modifications to their turbo or supercharged mustang applications.

Amazing quality!!

These Iridium Plugs really make all the difference! NGK is an awesome brand as always but once you start adding Boost and get a performance tune you'll notice that your car is gonna be running insanely ...
rich and idle pretty rough. In my case I also noticed a small decrease in power as well because of my high altitude. I knew that I needed to get a better plug that would provide a stronger faster spark to be able to keep up with the new performance tune and added Boost. I purchased these NGK Iridium plugs with an 8 heat rating and it has definitely been a night and day difference! I have all my power back and my motor is running stronger and smoother than it ever has before! I've always been a huge fan of NGK plugs and they've never let me down. These new Iridium plugs have actually impressed me more than usual, if it's at all possible I feel that they have stepped up their game once again!!

3 Questions / 4 Answers

Ford racing 750 HP Kit I have 2012 Shelby GT 500 in the process of installing a ford racing 750 HP Supercharger Kit with long tube headers catted X Pipes and manga flow cat back system! Which spark plugs and coil on plug kits can I use to complement this setup
Thanks

RajunCajun

These NGK Iridium IX spark plugs are a colder than stock heat range on your 2012 GT500 and are recommended for an increased boost application.

AMSam

These NGK Iridium IX spark plugs have a colder than stock heat range and therefore are recommended for an increased boost application.

What is the gap for a 2014 GT500 with a 2.4 Metco Pulley, a Ford Racing Cobra Throttle Body, and a JLT Big Air Intake with BAMA tunes?

Ray80

We would recommend the stock gap for your GT500 for most applications, however, with the modifications on your vehicle, we would recommend using the gap which was specified when Bama programmed your tune.

The spark plugs do come pre-gapped; however, with any spark plug - these included - it is highly recommended that each plug be checked prior to installation to ensure that everything is as it should be!

I added these plugs with a pulley/idler and cai tuner kit, as well as afco racing radiator and 170 thermostat. Very pleased with the responsiveness of the engine now and the plugs fit very well for the modifications done. Would recommend these plugs for anyone looking to do minor modifications to their turbo or supercharged mustang applications.

These Iridium Plugs really make all the difference! NGK is an awesome brand as always but once you start adding Boost and get a performance tune you'll notice that your car is gonna be running insanely rich and idle pretty rough. In my case I also noticed a small decrease in power as well because of my high altitude. I knew that I needed to get a better plug that would provide a stronger faster spark to be able to keep up with the new performance tune and added Boost. I purchased these NGK Iridium plugs with an 8 heat rating and it has definitely been a night and day difference! I have all my power back and my motor is running stronger and smoother than it ever has before! I've always been a huge fan of NGK plugs and they've never let me down. These new Iridium plugs have actually impressed me more than usual, if it's at all possible I feel that they have stepped up their game once again!!

I bought these a wile ago and they work amazing well. I was having some idling issues and these completely fixed that as well as adding to the responsiveness of my car. My only complaint is that they are a little pricey, other than that I love them. Great job AM!

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